电-Fenton法处理甲醛废水

研究了IrO2／Ta2O5电极做阳极、自制石墨电极做阴极电-Fenton法对低浓度甲醛废水处理方法。并对影响因素进行讨论。结果显示在pH为3,Na2SO4浓度8mg/L,FeSO4浓度0．4mmo／L,通以20ml／min／L空气,电流密度10mA/cm^2甲醛去除率可达到87％。     

间接原子吸收法测定水中硫化物

通过将水样酸化后转化成硫化氢,用氮气带出,被含有定量且过量的铜离子吸收液吸收。分离沉淀后,通过测定上清液中剩余的铜离子,对硫进行间接定量。方法检出限为0.2 mg·L^-1,对实际水样进行分析,加标回收率在90%～95%之间,结果令人满意。     

Surface properties of bacteria from activated sludge in relation to bioflocculation

Two bacterial stains were isolated from the activated sludge and identified as Leucobacter sp.and Alcaligenes faecalis by 16S rDNA sequencing.Pure cultures of these two strains,representing well or poorly settled bacteria,were used to investigate the mechanism of bioflocculation in activated sludge.Based on the analyses of the characteristics of cells hydrophobicity,ζ-potential,flocculation ability and extracellular polymeric substance (EPS) composition under different growth stages,it was found that the ratio of cell EPS protein had the highly influence on ζ-potential and hydrophobicity,which were important factors to bioflocculation.Cellulase and Proteinase K could destroy the extracellular biopolymer and resulted in a decrease in the hydrophobicity and ζ-potential.However,in our study,the flocculation characteristics exhibited differently in relation to cellulase and Proteinase K.Flocculation of cells treated with cellulase and Proteinase K decreased sharply,and then recovered quickly in cellulase treatment,while cells treated with Proteinase K showed no sign of recovery.This reveals that the presence of protein in extracellular biopolymer plays an important role to the bioflocculation of cells.     

Effects of metal lead on growth and mycorrhizae of an invasive plant species （Solidago canadensis L.）

It is less known whether and how soil metal lead (Pb) impacts the invasion of exotic plants.A greenhouse experiment was conducted to estimate the effects of lead on the growth and mycorrhizae of an invasive species(Solidago canadensis L.)in a microcosm system. Each microcosm unit was separated into HOST and TEST compartments by a replaceable mesh screen that allowed arbuscular mycorrhizal (AM) fungal hyphae rather than plant roots to grow into the TEST compartments.Three Pb levels(control,300,and 600 mg/kg soil)were used in this study to simulate ambient soil and two pollution sites where S. canadensis grows.Mycorrhizal inoculum comprised five indigenous arbuscular mycorrhizal fungal species (Glomus mosseae,Glomus versiform,Glomus diaphanum,Glomus geosporum,and Glomus etunicatum).The 15N isotope tracer was used to quantify the mycorrhizally mediated nitrogen acquisition of plants.The results showed that S. canadensis was highly dependent on mvcOrrhizae.The Pb additions significantly decreased biomass and arbuscular mycorrhizal colonization(root length colonized,RLC%) but did not affect spore numbers,N(including total N and 15N) and P uptake.The facilitating efficiency of mycorrhizae on nutrient acquisition was promoted by Pb treatments.The Pb was mostly sequestered in belowground of plant (root and rhizome).The results suggest that the high efficiency of mycorrhizae on nutrient uptake mightgive S. canadensis a great advantage over native species in Pb polluted softs.     

钙化物在废弃物基活性炭制备过程中的影响

研究了以城市垃圾中3种典型的固体有机废弃物——锯木屑、纸张和塑料的热解产物（分别简称木炭、纸炭和塑料热解物）为原料,水蒸气为活化剂制备废弃物基活性炭时钙化物含量对活化过程、活性炭吸附性能（以碘值表征）及其孔结构的影响。结果表明,钙化物可加快活化反应的速度,且钙化物含量在1.5%时活化反应速度即已不再随钙化物含量的增加而增加;活性炭的吸附性能则随钙化物含量的增加而减少,同时钙化物对活性炭的孔径分布基本无影响,但降低了活性炭的比表面积、微孔孔容及中孔孔容;钙化物的2种前驱体（即CaO和Ca（OH）2）对活化过程具有相同的催化作用。     

内蒙古自然保护区生物多样性保护现状

内蒙古经过进多年的建设,已建立了202个自然保护区,由于多年来实行的是以抢救性保护为主的方针和政策,自然保护区建设数量增长较快,随之而来的“重数量轻质量、重建立轻管护”的问题也较为突出。本文仅是一个探索,希望能对自然保护区的生物多样性保护起到一个促进作用,推动自然保护区的可持续发展,文章还欠完善,希望引起同行的兴趣,共同探讨。     

延迟焦化装置的定量风险评估

通过长岭分公司延迟焦化装置的定量风险评估,明确了装置中的主要危险设备,量化出装置的整体风险水平,促进了企业的安全生产.     

氢化物发生原子荧光法测定地表水和饮用水中的痕量砷、汞、硒

文章研究了用SK-2002 AFS analyser氢化物发生原子荧光法测定地表水和饮用水中的砷、汞、硒的测定。在5％的酸度条件下加入5％硫脲＋5％抗坏血酸,20g／L的硼氢化钾为还原剂,调整仪器的空气和辅气流量及分析条件为文中条件,取水样中分别添加砷,汞,硒,使它们的浓度分别为2μg/L,0．4μg／L,4μg／L,连续测定12次,以砷,汞,硒的相对标准偏差分别为0．4％,1．1％,1．2％。取水样加入As,Hg,Se标准分别为2．0ng,0．6ng,4．0ng,测定的添加标准回收率分别为99．5％,97．5％,95．8％。研究结果表明,该方法操作简便,快速,灵敏,干扰少,检出限低等特点,适合于测定地表水和饮用水中砷,汞,硒的测定。     

西南喀斯特地区石漠化问题研究综述

喀斯特地区石漠化是在脆弱的生态地质背景基础上叠加了人类活动而出现的。西南地区的石漠化面积现仍约以2500km^2／a的速度进一步扩大。石漠化的生态治理工作的目的就是要在人为作用的干扰下,使这种逆向演替转变为顺向演替。石漠化治理思路设计的科学性、战略性、可行性决定了最后石漠化的治理结果。在喀斯特石漠化的治理中,要根据不同岩溶环境类型区及石漠化发育的不同程度和不同山地的立地条件,针对其特点,选择多种途径,运用恰当的恢复技术,制定出具体的开发治理措施,实行规模治理,以提高资源利用率,促进石漠化生态环境的综合治理。     

Effects of humic acid fractions with different polarities on photodegradation of 2, 4-D in aqueous environments

Four fractions (A, B, C, and D) of humic acids (HAs) were separated based on the polarity from weak to strong. UV-vis absorption and Fourier transform infrared spectroscopy (FTIR) analysis show that the fractions C and Dpossessedmore aromatic C=C content. The influences of HAs and their fractions on the photolysis were investigated by the photodegradation of 2,4-D solutions under simulated solar light irradiation. The degradation rate of 2,4-D was found to decrease in the presence of bulk HAs or their fractions especially at high HAs concentration. The fractions of strong polarity C and D retarded the degradation rate more than the fractions of weak polarity A and B. This could be attributed to the different absorption intensity of the four HAs fractions in the order of D ⩾ C > A > B, and the stronger π-π electron donor-acceptor interactions between the strong polar fractions and 2,4-D.